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EDITORIAL

What Is it About Linux?

Here’s a riddle for you to use to amuse your friends: What do Windows CE, Java and Linux all have in common? Answer: Not one of them was originally conceived for use in real-time and embedded systems.

No, Windows CE was originally designed for use in a generation of half-laptop-size machines that never took off in the market. It then went through a couple of versions before it became the very popular embedded operating system we know today. Java, of course, was to be the “write once run anywhere” programming paradigm, which by virtue of its virtual machine seemed to disqualify it from use in embedded and real-time applications. Linux arose out of the frustration of the programming community with the fragmentation and proprietary turf wars around Unix. It was to be “Unix the way we always wanted it to be.” Unix was at the time a very desktop-oriented operating system with a number of disparate attempts to give it real-time characteristics.

Of these three software entities, two are largely controlled by single companies: Microsoft and Sun Microsystems. As such, their evolution has tended to be guided by the interests and perspectives of those companies. Even “independent” Java vendors must be guided by much of what Sun decides. There are variations among kernel code for processor support and even supersets and subsets of APIs, which result in programming paradigms that have a single name but many variants under that one tent.

Linux is different if not absolutely so. It did not arise from a corporate womb; it was started by a guy who wanted to do it because it seemed a right and useful thing to do. He did not claim to be the single fount of wisdom and therefore did not try to own it all or control every aspect of its development. The result has been a path of evolution of almost biological character with Linus Torvalds as the “intelligent designer” who knew when to keep his mitts off it and when to make pronouncements about it.

That benign shepherding has spawned a community of highly motivated intelligent and enthusiastic participants who have not only refined Linux but also made it possible for it to migrate from the desktop and mainframe worlds into telecommunications systems, mobile phones and myriad embedded devices—largely with a single code base that spans processor architectures and application domains.

Of course there are differences among commercial distributions, which are actually open source code that has been brought together, verified and tested and is given support by the Red Hats, MontaVistas and SuSes of this world. What you are buying with one of these distributions is not a license to someone’s proprietary code, but the assurance that the code that is available for free has been checked out to work together and that there is a number to call for support—so you don’t have to start from scratch.

Linux has survived dark threats by companies that claimed original rights to it and by others who claimed that they had found their own misappropriated source code in the listings and whose legal action would bring this whole unruly gaggle of software fanatics to heel and impose respectable fees. Harrumph! Still, Linux goes on and is today doubtless so valuable to the growing new world software infrastructure that such efforts will never get anywhere.

Then there’s that penguin.

“Serious” marketing people have dismissed it as silly or frivolous or cutesy, but little chubby Tux is the perfect symbol for what the Linux community has been about. Anyone who develops a Linux-based product is free to use the penguin at no charge. The origin of Tux is said to be connected to Linus Torvalds’ affection for penguins. Here again, we have initiation without insistence on control—just influencing direction.

Today, Tux is universally recognized as the symbol for Linux and all this was done without charge by Larry Ewing using GIMP (GNU Image Manipulation Program) that comes with many GNU Linux distributions. And yet for all this seemingly free and easy attitude, Linux developers are creating compelling applications and products, many are becoming quite prosperous, and Linux itself is becoming an indispensable part of the world’s technology infrastructure.

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